Microstructural, optical and gas sensing characterization of laser ablated nanostructured ceria thin films

Ceria thin films are deposited on quartz substrates at various substrate temperatures (923-1073 K) with optimized deposition parameters by using pulsed laser deposition technique. Prepared thin films are characterized by X-ray diffraction (XRD), atomic force microscopy, Raman spectroscopy and transmission UV-Vis spectroscopy to study the effect of substrate temperature. The XRD studies reveal the polycrystalline nature of CeO2 thin films. The preferred orientation is observed along (111) plane. The atomic force microscopy studies show the formation of uniform and dense nanocrystallites with smooth surface morphology. The RMS roughness of the thin film is increased with the increase of substrate temperature. The formation of CeO2 with cubic structure is confirmed with Raman peak appeared at 463 cm(-1) due to the F-2g active mode. The optical transmission studies reveal that the optical band gap decrease with increasing the substrate temperature. Acetone gas sensing characterization has been carried out at elevated temperatures.